Briefcase



FIG. 1 is a perspective view of a briefcase showing our new design.

FIG. 2 is front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is left side view thereof;

FIG. 5 is right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines on the straps and logo patch indicate stitching and are part of the claimed design. All other broken lines in the figures are illustrative of environment and form no part of the claimed design. 

The ornamental design for a briefcase, as shown and described. 